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tannin
tannin tannic acid, or gallotannic acid, astringent vegetable product found in a wide variety of plants. Sources include the bark of oak, hemlock, chestnut, and mangrove; the leaves of certain sumacs; and plant galls. Tannin is also present in tea, coffee, and walnuts. A solution of tannic acid is obtained from one of these natural sources by extraction with hot water; in particular, gallotannic acid is obtained from plant gall. Tannin varies somewhat in composition, having the approximate empirical formula C 76 H 52 O 46 . Tannic acid is a colorless to pale yellow solid; it is believed to be a glucoside in which each of the five hydroxyl groups of the glucose molecule is esterified with a molecule of digallic acid. Tannin is used in tanning animal skins to make leather; it transforms certain proteins of animal tissue into compounds that resist decomposition. It is also used in manufacturing inks, as a mordant in dyeing, and in medicine as an astringent and for treatment of burns. |
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"tannin." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "tannin." The Columbia Encyclopedia, 6th ed.. 2011. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1E1-tannin-t.html "tannin." The Columbia Encyclopedia, 6th ed.. 2011. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-tannin-t.html |
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tannin
tannin One of a group of complex organic chemicals commonly found in leaves, unripe fruits, and the bark of trees. Their function is uncertain: the unpleasant taste may discourage grazing animals, or they may help form barriers against the entry of pathogens. Some tannins have commercial uses, notably in the production of leather and ink.
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"tannin." A Dictionary of Biology. 2004. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "tannin." A Dictionary of Biology. 2004. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O6-tannin.html "tannin." A Dictionary of Biology. 2004. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-tannin.html |
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tannin
tannin A generic term for complex, non-nitrogenous compounds containing phenols, glycosides, or hydroxy acids, which occur widely in plants. They are toxic substances with astringent properties, whose principal function appears to be to render plant tissues unpalatable to herbivores.
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MICHAEL ALLABY. "tannin." A Dictionary of Ecology. 2004. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "tannin." A Dictionary of Ecology. 2004. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O14-tannin.html MICHAEL ALLABY. "tannin." A Dictionary of Ecology. 2004. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O14-tannin.html |
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tannin
tannin A generic term for complex, non-nitrogenous compounds containing phenols, glycosides, or hydroxy acids, which occur widely in plants. They are toxic substances with astringent properties, whose principal function appears to be to render plant tissues unpalatable to herbivores.
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Cite this article
MICHAEL ALLABY. "tannin." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. MICHAEL ALLABY. "tannin." A Dictionary of Plant Sciences. 1998. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O7-tannin.html MICHAEL ALLABY. "tannin." A Dictionary of Plant Sciences. 1998. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O7-tannin.html |
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tannin
tan·nin / ˈtanin/ • n. a yellowish or brownish bitter-tasting organic substance present in some galls, barks, and other plant tissues, consisting of derivatives of gallic acid, used in leather production and ink manufacture. |
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"tannin." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "tannin." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O999-tannin.html "tannin." The Oxford Pocket Dictionary of Current English. 2009. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-tannin.html |
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tannin
tannin (tannic acid) Any of a group of complex organic compounds derived from tree bark, roots and galls, unripe fruit, tea and coffee. Tannin is used in tanning to cure hides and make leather, in inks and dyes, and as an astringent in medicine.
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"tannin." World Encyclopedia. 2005. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "tannin." World Encyclopedia. 2005. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O142-tannin.html "tannin." World Encyclopedia. 2005. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-tannin.html |
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tannin
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T. F. HOAD. "tannin." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "tannin." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O27-tannin.html T. F. HOAD. "tannin." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-tannin.html |
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tannin
tannin
•tannin
•antivenin, Lenin
•Kalinin • linen • bedlinen
•underlinen • feminine
•Cronin, phone-in, ronin, serotonin
•Bakunin • run-in • melanin • santonin
•crankpin • backspin • hatpin
•tenpin • hairpin • tailspin • wheelspin
•Crippen, pippin
•stickpin • kingpin • Crispin • linchpin
•tiepin • topspin • clothespin
•lupin, lupine
•pushpin • terrapin • Turpin • Karin
•chagrin • aspirin • Catrin • Kathryn
•Gagarin
•Erin, Perrin, serin
•Sanhedrin • epinephrine • dextrin
•brethren • Montenegrin • pyrethrin
•peregrine
•Corin, florin, foreign
•doctrine • sovereign • Aldrin
•Paludrine • murrain
•Kirin, stearin
•Lohengrin
•burin, urine
•tambourin • mandarin • warfarin
•saccharin, saccharine
•tamarin • Catherine
•navarin, savarin
•culverin • Mazarin
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"tannin." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 27 May. 2012 <http://www.encyclopedia.com>. "tannin." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (May 27, 2012). http://www.encyclopedia.com/doc/1O233-tannin.html "tannin." Oxford Dictionary of Rhymes. 2007. Retrieved May 27, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-tannin.html |
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